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  <title id="eu135496">System Catalogs</title>
  <body>
    <p>This reference describes the Greenplum Database system catalog tables and views. System
      tables prefixed with <codeph>gp_</codeph> relate to the parallel features of Greenplum
      Database. Tables prefixed with <codeph>pg_</codeph> are either standard PostgreSQL system
      catalog tables supported in Greenplum Database, or are related to features Greenplum that
      provides to enhance PostgreSQL for data warehousing workloads. Note that the global system
      catalog for Greenplum Database resides on the master instance.</p>
    <note type="warning"> Changes to Greenplum Database system
      catalog tables or views are not supported. If a catalog table or view is changed<ph
        otherprops="pivotal"> by the customer</ph>, the <ph otherprops="pivotal">Tanzu Greenplum
       cluster is not supported. The </ph>cluster must be reinitialized and restored<ph
        otherprops="pivotal"> by the customer</ph>.</note>
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